ESSENTIAL ROLE OF SURFACE HYDROXYLS FOR THE STABILIZATION AND CATALYTIC ACTIVITY OF TiO2-SUPPORTED GOLD NANOPARTICLES

Conference · Thu Jan 01 04:00:00 EST 2009

OSTI ID:972304

Veith, Gabriel M ^[1]; Lupini, Andrew R ^[1]; Dudney, Nancy J ^[1]

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1. ORNL

We report the investigation of titania supported gold catalysts prepared by magnetron sputtering. Catalysts grown on natural fumed titania were structurally unstable resulting in the rapid coarsening of 2.3 nm gold clusters into large ~20 nm gold clusters in a few days at room temperature under normal atmospheric conditions. However, treating the titania support powder to a mock-deposition-precipitation process, at pH 4 or pH 10, followed by the subsequent deposition of gold onto this treated powder produced a remarkable enhancement in gold particle stability and a 20-40 fold enhancement of catalytic activity respectively. This enhancement can not be attributed to the formation of oxygen vacancies on the TiO2 surface. Instead, it appears to be associated with the formation of strongly bound hydroxyl species on the TiO2 surface. The formation of surface hydroxyls during the deposition-precipitation method is coincidental and contributes significantly to the properties of Au/TiO2 catalysts.

• Research Organization: Oak Ridge National Laboratory (ORNL); Center for Nanophase Materials Sciences
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 972304
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CATALYST SUPPORTS
CATALYSTS
CATALYTIC EFFECTS
DEPOSITION
GOLD
SAMPLE PREPARATION
STABILITY
STABILIZATION
TITANIUM OXIDES
VACANCIES